1. Field of the Invention
The present invention relates to devices for performing percutaneous arthroscopic and other endoscopic or laparoscopic surgeries and, more specifically, to surgical devices such as cannulas and “portal holder devices” having a plurality of biasing fins that converge to define a flexible opening that is capable of closing to form a substantially impermeable seal, and surgical device deployment tools for the deployment of such devices during a surgical procedure. The aforementioned convergence of the fins, in one embodiment, occurs during insertion proximally to limit fluid leakage when not being utilized and diverge distally to retract soft tissues and improve visualization. This concept utilizes, in addition to the features of the devices discussed herein, the inherent soft tissue and hydrostatic pressure to limit leakage. Numerous open (non-arthroscopic) applications also exist for this invention in that the low-profile insertion of the biasing fins improves surgical exposure and visualization. In open applications, the biasing fins have greater divergence for direct visualization.
2. Description of Related Art Including Information Disclosed under 37 CFR 1.97 and 1.98
Traditional minimally-invasive arthroscopic surgeries are performed using a cannula device to penetrate small incisions in the patient's skin and outer tissue, creating a port through which surgical tools may be passed to allow access to the underlying structure of interest. For example, in shoulder arthroscopy, the procedure is performed through “portals” in the patient's skin. These portals are formed from small incisions, generally about ½ of an inch to an inch long in the skin, and are located over particular areas of the joint that the surgeon will need to operate upon. Cannulas are then inserted into the portals so that instruments can easily be placed in the shoulder joint. Shoulder arthroscopy itself involves inserting a specially designed video camera with a fiber optic light source into the shoulder joint so that the anatomic structures of the joint can be seen. Instruments that have been specially designed to remove inflamed tissue, attach sutures to bone, and repair torn tendons and ligaments are then used to operate inside the shoulder.
The area between the skin tissue and shoulder joint is quite small. Consequently, it is necessary to “inflate” the area by pumping an irrigation fluid (e.g. saline) into the joint under pressure. In laparoscopic surgical procedures, carbon dioxide in gaseous form may be utilized as an insufflating agent to perform a similar function. The pressure produced by the irrigation fluid pushes the tissue outward from the joint and allows greater room for manipulation of the arthroscopic camera and other surgical tools. However, the actual working angle of the tools is ultimately determined by the length and inner diameter of the cannula. Heavy patients or patients with large amounts of skin and other tissue covering the joint require a longer cannula to penetrate the tissue sufficiently for the procedure. This increased cannula length decreases the working angle of the tools at the joint, limiting the ability of the surgeon to perform the procedure. Although this angle may be improved by increasing the inner diameter of the cannula, there are realistic limits on the useable diameter. For example, the diameter can only be increased by a small amount or else it would effectively eliminate any benefit of conducting the arthroscopic procedure as the portal size could become the equivalent of a large incision as performed in traditional surgery.
The aforementioned irrigation fluid and/or gases pumped into a joint during a surgical procedure must remain sealed within said joint to maintain sufficient pressure and space for the movement of surgical instruments. Various devices and techniques have been employed in the prior art to maintain such seal. Most typically, a series of annular seals mounted within a cannula, at an end of said cannula proximal to the patient, serve to prevent leakage of fluid out of the joint during a surgical procedure. However, the usage of such annular seals for fluid retention has drawbacks in that undesirable leakage tends to occur as surgical instruments passing through the cannula are manipulated during a procedure. Further undesired leakage also tends to occur upon the insertion and/or removal of surgical instruments to/from the cannula during a procedure.
What is needed is a surgical portal device that is capable of retracting the tissue through which it penetrates, that is relatively simple to insert and remove so as to minimize tissue damage to the patient, that includes a novel means for incorporating a shape memory alloy into its design that is easy to store, use, remove, and reuse (or dispose of), and that provides for enhanced fluid retention. The surgical portal device disclosed herein satisfies these needs and others as will become apparent to one of ordinary skill after a careful study of the detailed description and embodiments.
The above figures are provided for the purpose of illustration and description only, and are not intended to define the limits of the disclosed invention. Use of the same reference number in multiple figures is intended to designate the same or similar parts. Furthermore, if and when the terms “top,” “bottom,” “first,” “second,” “upper,” “lower,” “height,” “width,” “length,” “end,” “side,” “horizontal,” “vertical,” and similar terms are used herein, it should be understood that these terms have reference only to the structure shown in the drawing and are utilized only to facilitate describing the particular embodiment. The extension of the figures with respect to number, position, relationship, and dimensions of the parts to form the preferred embodiment will be explained or will be within the skill of the art after the following teachings of the present invention have been read and understood.